1. Field of the Invention
The present invention relates to an automotive air conditioner, and more particularly to an automotive air conditioner for front and rear seating areas of an automotive vehicle.
2. Description of the Related Art
With conventional, automotive air conditioners, particularly those for leisure vehicles (recreational vehicles or RV's) such as box wagon-types or station wagon-types in which the interior is designed to be spacious, even though the number of passengers increases so that a cooling load also increases an air-conditioning system is composed of a single system having a large capacity which can cope with the load for air-conditioning.
Namely, as shown in FIG. 3, the air conditioner used in an RV vehicle is composed of a compressor 101 disposed in the vicinity of an engine (not shown), a condenser 102 disposed in the front of an engine compartment, a cooler unit 103 for a front seating area, and a cooler unit 104 for a rear seating area disposed in parallel therewith, and the like. The compressor 101 in this air conditioner is designed to be capable of coping with the cooling load for the entire passenger compartment. Moreover, the cooler unit here means a unit composed of an evaporator, an expansion valve and the like on the passenger compartment side.
Hence, when the number of passengers is small, the compressor 101 has extra capacity such that a large amount of energy can be consumed and the system is uneconomical. Also, the compressor 101 is disposed in the engine compartment, so that the distance between the compressor 101 and the cooler unit 104 for the rear seating area is long. Accordingly, refrigerant tubing for connecting them are long, resulting in an increase in refrigerant flow resistance. Consequently, the system suffers from a problem in that capacity loss increases. Also, the air conditioner is frequently engaged or disengaged by a clutch (not shown) for coupling the engine with the compressor 101. In this case, the system suffers from a problem in that the engine load is abruptly changed which generates vibrations. Also, the total length of the refrigerant tubing for connecting the condenser 102 or the cooler units 103 and 104 to the compressor 101 increases, so that refrigerating machine oil is stagnant in the refrigerant tubing when the air-conditioner is not used. Thus, the system suffers from a problem in that it is likely to cause insufficient lubrication upon the start of the compressor.